Amazon offers the GoPro HERO6 Black 4K Action Camera for $399.99 with free shipping. That's $49 under our Cyber Monday mention (although that included a $75 B&H gift card) and the lowest outright price we've seen. (It's the best deal now by $59, although most retailers charge upwards of $479.) It's waterproof to 33 feet without a housing and features a 2" touchscreen LCD, up to 4K video recording at 60fps, 12-megapixel still image resolution, three microphones, 5GHz WiFi, Bluetooth, GPS (with data overlay via the free Quik desktop app), microSDXC card slot, micro HDMI, and rechargeable Li-ion battery.

Update: The price has dropped to $399.